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docs/buildings/oat-farm.md

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+# Oat Farm
+
+**Entity Type:** Building
+
+## Properties
+
+| Field | Value |
+|-------|-------|
+| Category | Production / Agriculture |
+| Required Tier | [Tier I](../population-tiers/tier-i.md) |
+| Construction Time | Instant |
+| Cycle Time | 60 seconds |
+
+## Description
+
+Produces Oats; uses field modules; aqueduct optional.
+
+## Costs
+
+**Build Cost:** 3 Timber
+
+**Maintenance:** -4 gold/min, 3 Tier I workers
+
+## Placement
+
+| Requirement | Value |
+|-------------|-------|
+| Road Required | Yes |
+| Warehouse Required | Yes |
+| Constraints | Requires fields; requires relevant fertility (oat/grain) |
+
+## Production
+
+**Input:** None
+
+**Output:** [Oats](../goods/oats.md)
+
+## Production Chain
+
+[Porridge Chain](../production-chains/porridge.md)
+
+## Usage Patterns
+
+Keep fields compact; warehouse nearby; consider aqueduct support.
+
+## Common Pitfalls
+
+Insufficient fields/fertility leads to low output; long travel distance leads to apparent underproduction.